Trimethylated histone H3 lysine 27 (H3K27me3) is a repressive histone marker that regulates a variety of developmental processes, including those that determine flowering time. However, relatively little is known about the mechanism of how H3K27me3 is recognized to regulate transcription. Here, we identified BAH domain‐containing transcriptional regulator 1 (BDT1) as an H3K27me3 reader. BDT1 is responsible for preventing flowering by suppressing the expression of flowering genes. Mutation of the H3K27me3 recognition sites in the BAH domain disrupted the binding of BDT1 to H3K27me3, leading to de‐repression of H3K27me3‐enriched flowering genes and an early‐flowering phenotype. We also found that BDT1 interacts with a family of PHD finger‐containing proteins, which we named PHD1–6, and with CPL2, a Pol II carboxyl terminal domain (CTD) phosphatase responsible for transcriptional repression. Pull‐down assays showed that the PHD finger‐containing proteins can enhance the binding of BDT1 to the H3K27me3 peptide. Mutations in all of the PHD genes caused increased expression of flowering genes and an early‐flowering phenotype. This study suggests that the binding of BDT1 to the H3K27me3 peptide, which is enhanced by PHD proteins, is critical for preventing early flowering.

Two energetic compounds, [Zn(H2O)6](PA)2·3H2O (1) and [Zn(ATZ)3](PA)2·2.5H2O]n (2), were synthesized based on 4‐amino‐1,2,4‐triazole (ATZ) and picrate (PA), and characterized by elemental analysis and Fourier transform infrared (FT‐IR) spectroscopy. The crystallographic data showed that the crystals of 1 and 2 belong to the monoclinic space group P21/n and the triclinic space group P$\bar{1}$, respectively. Furthermore, the ZnII cations are six‐coordinated with six oxygen atoms from crystal water molecules for 1 and six nitrogen atoms from ATZ for 2, and exhibit distorted octahedral configurations. Thermal decomposition mechanisms were determined based on differential scanning calorimeter (DSC) curve corresponding to thermogravimetry‐derivative thermogravimetry (TG‐DTG) curves and kinetic parameters of the first exothermic process were studied by using Kissinger's and Ozawa's method. The energies of the impact sensitivities were 27.8 J for 2 and far greater than 29.4 J for 1. In addition, the experiment found the heats of combustion were –6.53 MJ·kg–1 for 1 and –11.33 MJ·kg–1 for 2 by oxygen bomb calorimeter. Therefore, compound 2 can improve the explosion performance and can maybe regarded as the less toxicity energy additive for the explosives and propellant formulations.

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The novel coordination compound of [Mg(H 2 O) 6 ](ATZ) 2 (PA) 2 (1) was synthesized by using 4-amino-1,2,4-triazole (ATZ) and picrate (PA) and characterized by elemental analysis and FT-IR spectrum. The crystal structure was determined by X-ray single crystal diffraction and the crystallographic data showed the crystal belong to triclinic, pertains to P-1 space group, α = 6.980(4)Å, b = 7.047(4)Å, c = 15.603(10)Å, α = 83.84(2) • , β = 81.99(1) • and γ = 82.66(2) • . The Mg(II) ion is six-coordinated with six oxygen atoms from crystal water molecules and exhibits distorted-octahedral configuration. Furthermore, thermal analysis indicated a melting point peak at 133.5 • C, and then three main exothermic processes occurred as shown in the differential scanning calorimeter (DSC) curve corresponding to thermogravimetry-derivative thermogravimetry (TG-DTG) curves. The kinetic parameters of the first exothermic process were studied by using Kissinger's method and Ozawa's method. The enthalpy of formation, critical temperature of thermal explosion, entropy of activation ( S / = ), enthalpy of activation ( H / = ), and free energy of activation ( G / = ) were calculated and obtained as -3172.15 kJ·mol −1 , 506.92 K, -160.36 kJ·mol −1 , 134.91 J·(·Kmol) −1 and 213.73 kJ· mol −1 , respectively. The flame and impact sensitivities measuring results showed the 50% firing heights were 9.6 cm and 78.5 cm ( = 38.5 J), respectively.